can you please quote the FULL hadith. whats with the shia hadith? are you shia? are you? anyway, it does not mean that the world will already be "...illuminated by the light of Allah..." and "...the only faith will be that of Allah..." otherwise what will be the need to conquer the world when it already has been conquered and islam will be prevailent? it means that WHEN Al-Mahdi will conquer the world....THEN it will be "...illuminated by the light of Allah..." and "...the only faith will be that of Allah...". This is so obvious that a child could understand it!